Every PV inverter and electricity meter available on the market is tested according to the standards which are valid for the individual product. Nevertheless, malfunctions of some electronic electricity meters have been detected, when used in conjunction with special PV inverters. In one case, the meter displayed only 85% of the real energy fed into the public grid by the PV inverter [1]. The meter was checked in a calibration laboratory without negative results. Investigations by ISET have shown that the RF ripple current of the inverter influenced the meter. In most inverters, the frequency of the ripple current lies between 3 kHz and 150 kHz. Unfortunately, no emission and immunity requirements exist for inverters and meters within this frequency range [2] [3] [4]. ISET/IWES has developed a special test setup, which can simulate electric ripple currents, similar to those generated by inverters. Investigations on inverter EMC test setups with low differential mode impedance AC artificial mains networks (AMN) are in progress.

24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 3695-3698